Field of the Invention
The present invention relates to a printing apparatus, a control method therefor, and a storage medium.
Description of the Related Art
There is known an MFP which is a printing apparatus that carries out a printing process using obtained image data. The MFP has a printer unit which carries out the printing process and a control unit which controls component elements of the MFP including the printer unit. The control unit obtains a variety of information on, for example, an operating status of the printer unit from the printer unit through data communications to control the printer unit. In the MFP, the same communication speed needs to be set for the control unit and the printer unit so as to enable data communications between the control unit and the printer unit. Accordingly, in the MFP, a matching process is carried out to match the communication speed of the control unit to that of the printer unit at, for example, start-up of the MFP. In this matching process, first, a first communication speed which is relatively low is set for each of the control unit and the printer unit. After that, when it is acknowledged through a communication at the first communications speed that it is possible to set a higher communications speed, a second communication speed higher than the first communication speed is set for each of the control unit and the printer unit. As a result, the same and high communication speed is set for the control unit and the printer unit, and this enables high-speed data communications between the control unit and the printer unit.
The MFP is equipped with a monitoring unit which monitors whether or not the control unit is normally operating, and upon detecting an abnormality in the control unit, the monitoring unit forcefully resets the control unit (see, for example, Japanese Laid-Open Patent Publication (Kokai) No. 2015-153343). When the control unit is reset by the monitoring unit, the first communication speed is set as the communication speed for the control unit as with the case at start-up of the MFP. Namely, in the MFP, the first communication speed is set again for the control unit while the second communication speed is still set for the printer unit. Thus, in the MFP, to match the communication speed of the control unit to that of the printer unit, the control unit sends a setting request signal, which requests setting of a communication speed, to the printer unit so that the communication speed for the printer unit can be changed to the first communication speed.
Since the first communication speed is set for the control unit at this time, the control unit sends the setting request signal through the communication at the first communication speed. However, since the second communication speed is still set for the printer unit, the printer unit cannot receive the setting request signal, and hence the communication speed for the printer unit is not changed to the first communication speed. As a result, a problem arises because communication between the control unit and the printer unit becomes impossible.